Layers of the Bladder and What Can Go Wrong

Layers of the Bladder and What Can Go Wrong

I’ve got a bit of a different blog for you this month, because it has pictures! And not just any pictures. I’ve had my coloured pencils out and have drawn them for you myself! We’re going to be learning all about the structure of the bladder and finding out why my decision not to take any exams in Art was probably for the best.

As most of you are probably aware, there is no single known cause or single known cure for interstitial cystitis. This makes it complex to diagnose and treat, which can be frustrating. However, if we actually look at how the bladder is made and the ways in which it can go wrong, it makes perfect sense that not everyone’s painful bladder symptoms, triggers and alleviating factors would be the same.

The bladder is not the same all the way through, but is made of different layers that serve different functions. See my excellent picture below:

The bladder is surrounded with a layer of fat called perivesical fat. I can’t find out much about its function, so I assume that it is there for cushioning and protection, as most organs have a layer of fat around them for these purposes. What I did learn is that you can sometimes see inflammatory changes in perivesical fat during CT scans on those with ketamine cystitis (KC) and that there can be changes to the perivesical fat in bladder cancer patients.

The next layer in can be either serosa or adventitia, depending on where on the bladder you look. Both serosa and adventitia are connective tissues, but serosa is slippery to allow some movement and adventitia is fixed to anchor things in place. The top of the bladder is covered with serosa, while most of the sides and lower section are surrounded with adventitia. You need adventitia to stop organs from moving around too much inside, but bits of some of them need to be slippery so that other bodily structures don’t stick to them.

Next is the detrusor muscle, which is where things start to get interesting. The detrusor muscle is itself split into layers, with the outer layers being longitudinal smooth muscle and the middle layer being circular smooth muscle. This allows squeeze in all directions. The job of the detrusor muscle is to relax while the bladder is filling (most of the time) and contract to squeeze urine out of the bladder (infrequently, but for several seconds at a time). Smooth muscle is outside of voluntary control, although because the detrusor muscle is activated to contact by a chain of events that are usually voluntary, it may feel as if we have control over it. In fact we only have voluntary control of the external urinary sphincter, which sends messages to the rest of the urinary system that we have decided to have a wee and allows this to happen.

If the detrusor muscle becomes unstable or overactive, it contracts before we have given it permission. We therefore get overactive bladder symptoms such as urgency, frequency, nocturia and urinary incontinence. Sometimes, involuntary contractions of the detrusor muscle can feel like painful spasms or even burning. Detrusor overactivity, also called detrusor hyperreflexia, is the most common cause of overactive bladder syndrome. On the other hand, if the detrusor muscle becomes lazy or fails, it will not contract even when we want it to and we get urinary retention. This is sometimes known as underactive bladder syndrome. It too can be uncomfortable or even painful, as the bladder becomes full, yet never empties in a satisfactory way.

It is interesting to note that the detrusor muscle is attached to the prostate in males and front of the vagina in females. This supports my own personal view that bladder problems often go hand in hand with Persistent Genital Arousal Disorder (PGAD).

After the detrusor muscle is the submucosa, also known as the lamina propria. This is a layer of loose connective tissue, interlaced with smooth muscle, blood vessels and nerves. The nerves signal to the brain when the bladder is full and receive signals from the brain letting the bladder know whether it has the green light to empty. In some interstitial cystitis patients, these nerves can become oversensitive in a process called neural upregulation. This means that the more pain or urgency is felt, the more easily pain and urgency will be felt, resulting in a vicious circle of more pain, easier pain, more pain, easier pain. Sometimes, this can endure even after the initial causes of interstitial cystitis have vanished. Pain medications and chronic pain counselling may assist in breaking such a cycle – indeed there is an App called Curable which specialises in helping people to cope with chronic pain conditions. I have not tried it, but it seems to get very positive reviews.

The submucosal layer of the bladder can also become inflamed. This may occur as a result of direct contact with urine when the protective innermost lining of the bladder has been compromised. Aloe vera is naturally anti-inflammatory and tissue regenerating, so Desert Harvest Super Strength Aloe Vera Capsules may help to reduce submucosal inflammation and repair damage to the tissue.

It is interesting to note that the bowel also has a submucosal layer, which becomes inflamed in conditions like Crohn’s Disease or ulcerative colitis and inflammatory bowel disease. People with interstitial cystitis often have digestive issues as well, which is why I always recommend strictly avoiding common allergens like gluten and dairy, as well as alcohol and sugary foods. If finances allow, I also highly recommend IgG food intolerance testing from Cambridge Nutritional Sciences to allow dietary changes to be personalised according to your own needs. Food intolerances can promote inflammatory reactions almost anywhere in the body and in my opinion this certainly includes the bladder.

The innermost layer on the first picture is an epithelial layer, which within the bladder is known as the urothelium or transitional epithelium. I will discuss that a bit later. You can see on the top picture that it contains folds. These are called ruggae and they unfurl as the bladder fills and fold back in as it empties.

The final thing I want to talk about in relation to the top picture is the triangular area known as the trigone. This is like a cone at the bottom of the bladder, which has its corners at the ureters. It funnels urine into the urethra. The trigone can become inflamed in a condition known as trignonitis. Trigonitis has much in common with interstitial cystitis, except that it only affects the lower portion of the bladder. In my opinion, trigonitis is more likely to be caused by damage to the innermost lining of the bladder than by muscular problems. I would suggest this would probably be as a result of ingested irritants like ascorbic acid, sudden hormonal changes and urinary tract infections, and as an early response to GAG layer damage (see later). D-Mannose and Desert Harvest Super Strength Aloe Vera Capsules may both be helpful for trigonitis, as might antibiotics be if infection is present. You can read more about trigonitis in this blog post and also over at the Sweet Cures website, which has this excellent post on the topic written by nutritionist Kathryn Marsden, who has suffered from the condition herself.

The next picture shows a zoomed in version of the urothelium and submucosa.

The urothelium, also known as transitional epithelium, consists of layers of epithelial cells. The very top ones are called umbrella cells; the next ones down are called intermediate cells; and the ones next to the submucosa are called basal cells. This layer of epithelium provides a barrier between urine and the other layers of the bladder. It is like a urine-proof coating that should prevent any waste products from re-entering the bloodstream. In my recent blog post about leaky gut, I discussed the tight junctions of the intestines and spoke about how they prevent harmful particles from escaping out of the intestines and into the bloodstream. The urothelium also has tight junctions whose function is to prevent water and solutes from leaking out of the bladder and back into the blood. Unfortunately, just as tight junctions in the gut can become slack and ‘leaky’, so too can the tight junctions of the bladder. It is thought that people suffering from interstitial cystitis may have compromised epithelial junctions. In my opinion, where there is a ‘leaky’ bladder, there is probably a leaky gut and vice versa. This is why I strongly recommend that people with interstitial cystitis should spend some time researching leaky gut and take the necessary steps to address it.

You will notice that the urothelium is covered with a GAG layer. GAG stands for glycosaminoglycan. Glycosaminoglycans are long molecules that strongly attract water, allowing them to create a mucous membrane over the urothelium. This provides an extra layer of protection that keeps urine out of contact with the urothelium, while the urothelium itself further protects the other layers of the bladder. The next picture shows the GAG layer in a bit more detail.

If the GAG layer of the bladder gets ‘holes’ in it, urine comes into contact with the urothelium beneath. This can cause irritation and inflammation that may result in pain and even ulceration. (Please note that ulceration is NOT necessary for diagnosis of interstitial cystitis and any practitioner who tells you otherwise is working with out of date criteria.) When the urothelial cells are not able to be replenished quickly enough, areas of the urothelium may become completely eroded away, leading to damage at the submucosal level. Not all interstitial cystitis patients display damage to the GAG layer, but plenty do. It is not known what causes the GAG layer to erode in the first place, but viral infections, substances in the urine, or the body’s immune system attacking its own tissues (an autoimmune disorder) could all be possibilities.

Desert Harvest Super Strength Aloe Vera Capsules naturally coat the bladder with a protective GAG layer. With consistent usage over several months, this may allow the GAG layer to be replenished, helping to reduce symptoms of pain, burning and urgency. In a survey of 614 interstitial cystitis sufferers, 92% self-reported ‘significant relief’ of at least some of their symptoms when taking Desert Harvest Aloe Vera. It is important to note that while 56% of these noticed improvements within the first four weeks, a further 27% needed up to three months. 12% took longer than three months and only 6% saw no improvements at all. This is why I emphasise to first time customers that patience and consistency are necessary! Glucosamine and chondroitin are both examples of glycosaminoglycans. Supplementing with Desert Harvest Glucosamine and Chondroitin may therefore also help to replace lost GAG molecules.

The final picture again shows the urothelial, submucosal and detrusor layers, but this time there are mast cells present. Mast cells are responsible for the production of histamine in the body. The purpose of histamine is to provoke an immune response such as inflammation or smooth muscle contraction when the body is exposed to an allergen. (The detrusor muscle is smooth muscle!) I wrote lots about mast cells and histamine in this blog post, so I won’t repeat it here. Suffice it to say that unusually high numbers of mast cells have often been found in these layers of the bladder in people with interstitial cystitis. This can contribute to the frequency, pain, burning and pressure that are so debilitating for those with IC.

Quercetin inhibits histamine release, decreases production of pro-inflammatory enzymes and inhibits mast cell activation. It may even help to heal a leaky gut wall (and thus, in my opinion, probably also a leaky bladder wall). Whereas damage to the GAG layer of the bladder can take quite a long time to heal, histamine release can be reduced quite quickly. I would encourage you to read my blog post Might You Have an Allergic Bladder for more information about histamine and mast cells and also to scroll to the bottom where you will see a message from a customer who wanted to share her experience.

I thought this would be a really simple blog post to research, but it turned out to be very time consuming and complex. Can you believe that people can’t even agree on how many layers the bladder has?! I’m indescribably bored with reading about them now! I’m sure you are too for that matter. Hopefully, now you know a little about each layer and how it works, you’ll be able to use your own symptoms and how they started to get a better idea of what exactly might be going wrong for you. And in turn, perhaps that will help you to put them right. Good luck!


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